Crushing mill



M. B. DAVIS CRUSHING MILL Jan. 30, 1934.

Filed March 18, 1929 4 Sheets-Sheet l agdi .5

M. B. DAVIS CRUSHING MILL Jan. 30, 1934.

Filed March 18. 1929 4 Sheets-Sheet 2 Jan. 30, 1934. M. B. DAVISCRUSHING MILL Filed March 18, 1929 4 Sheets-Sheet 3 M JZ/peEW Q50]? a0i/zwan z fi wai a Patented Jan. 3%, i934 FH'ATES CRUSHING MILL Mason B.Davis, Kendrick, Fla.

Application March 18, 1929. Serial No. 347,806

4 Claims. (01. 83-53) This invention relates to crushing and pulverizingapparatus and appliances and is illustrated herein as embodied in acrushing mill of the single roller type.

Such crushing mills comprise generally a rotary crushing roll and abreaker plate mounted in near proximity to the crushing roll andarranged to serve as a backing member or dam for presenting material tothe crushing roll during I rotation of the latter. The breaker plate iscustomarily spaced from the crushing roll to provide a passagewaybetween the two and is disposed in such a manner relatively to the rollthat the cross-sectional area of the passageway decreases downwardly. Bymeans of such a provision, material to be crushed or pulverized may beintroduced at the wide upper portion of the passageway and as it flowsdownwardly, it will be moved in the direction of the crushing roll inorder that particles of all sizes will be presented to the action of theroll. Heretofore, it has been generally customary to make the loadengaging surface of the breaker plate of a horizontally convex formationand to extend the lower portion of the plate beneath the crushing roll.Furthermore, it has been customary to mount the breaker plates of theprior art in such a manner that they are free to yield upon a certainamount of pressure being applied to them. The purpose of the yieldingaction vis to prevent breakage of the parts of the mill in the eventthat a heavy and particularly tough piece of material is introducedbetween the breaker plate and the roll.

While the prior art devices are doubtlessly satisfactory in operationand in performing the duties for which they are intended, it is anobject of the present invention to provide an improved single rollcrushing mill that is of such a strong and durable character that thebreaker plate will effectively resist all working strains or stressesthat are imparted to it, although the plate is rigidly mounted and isnot permitted to yield under any conditions.

It is pointed out, however, that although an important object of theinvention is as outlined above there are many important features andaspects of the invention which are applicable to crushing mills of thetype now generally employed as well as to the heavy and strong mill ofthe type disclosed in the present application.

In carrying out the above recited object of the invention, it was firstnecessary to obtain a breaker plate having a load engaging surface thatwould effectively and efficiently cooperate with the crushing roll insuch a manner as to reduce as far as possible the strains and stressescreated by the crushing operation. It is accordingly an importantfeature of the invention to disclose for such purpose a breakerplate,the load engaging surface of which is plain and flat and is disposedwith its upper edge more remote from the crushing roll than is its loweredge. Although such flat plain surfaces have heretofore been employed incrushing soft objects or in guiding material to a crusher, it isbelieved that the present applicant is the first to employ such asurface in connection with a heavy durable crushing mill of the typeunder discussion.

Another important feature of the invention consists in the provision ofan improved means for maintaining the breaker plate in a fixed positionrelatively to the crushing roll. As illustrated herein, this improvedmeans consists in the provision of interengaging portions formed on thebase of the breaker plate and on the support upon which the breakerplate is mounted. These interengaging projections may conveniently takethe form of serrations in order that the breaker plate may be adjustedrelatively to the rotary crushing roll, and it is contemplated providingadditional means for clamping the breaker plate securely in a desiredposition of adjustment so that it will under no conditions yield or moveduring the crushing operation.

Still another important feature of the invention, which is conducive tothe accomplishment of the recited object consists in mounting thebreaker plateand base in such a manner that the plate may be replacedrelatively to the base; Thus, in the operation of the will if a breaker.plate subjected to undue stress should crack or break it may be replacedwithout going to the necessity of replacing the heavy and more or lessexpensive base in connection with which the plate is employed.

It is customary in crushing mills of the type under discussion toprovide the crushing roll with a plurality of slugger knobs which extendoutwardly from the periphery of the roll and are utilized in strikingand crushing the material being operated upon. It is to be realized thatin a construction of the type here under discussion the slugger knobsmust be mounted in'an extremely strong and rigid manner and intheprovision of such a mounting there resides another important featureof the invention.

In the illustrated embodiment of the invention the slugger knobs arewedged against circumferential movement in a direction opposite to thedirection of the rotation of the roll, whereby the knobs are driven moretightly home each time they strike or engage the material to be crushed.In order to prevent radial displacement of the knobs they are dovetailedinto circumferential extending slots and the invention contemplatesmaking the slots slightly longer than the interfitting portions of theslugger knobs in order that the knobs may be removed with ease andfacility to permit replacement in the event that a knob becomes brokenor chipped beyond repair.

Still other objects and features of the invention will become apparentfrom a reading of the following specification in the light of theaccompanying drawings, in which- Figure 1 is a view in side elevation ofa single roll crusher having a breaker plate associated therewith;

Figure 2 is a view in side elevation of the single roll crusher andbreaker plate shown in Figure 1;

Figure 3 is a top plan view of the crusher and breaker plate of Figure1;

. Figure 4 is an enlarged fragmentary view showing the manner in whichthe breaker plate of the preceding figures is mounted;

Figure 5 is a vertical section through the breaker plate and the supporttherefor;

, Figure 6 is a fragmentary view of the crushing roll showing in topplan a slugger knob;

Figure 7 is a. View in section taken along the line 7-7 of Figure 6;

Figure 8 is a view in section taken along the line 8-8 of Figure 6; and

Figure 9 is a view in side elevation of a slugger knob.

As shown in Figures 1, 2, and 3 of the drawings, the rotary crushingmill comprises, generally speaking, a crushing or pulverizing roll 10mounted upon a horizontally extending shaft12 for rotation withinbearings 14, 16 located at opposite ends of the roll. One end of theshaft 12 is extended through the bearing 14 and has mounted upon itsouter extremity a driving gear 18 which meshes with a gear 20 that is inturn driven by a pulley 22 mounted upon a shaft 24.

As will be observed from an inspection of Figures l and 3, the shafts 12and 24 are mounted in bearings half of which are formed in base or framemembers 26, 28 located at opposite sides of the rotary crushing roll andarranged to extend parallel to one another and perpendicularly to theaxis of rotation of the roll.

The frame members 26, 28 for supporting the operating shafts 12 and 24are spaced apart asuitable distance and are mounted, as shown in Figure1, upon a concrete base C which is provided with a recess D forreceiving the lower portion of the pulley 22, a recess E for receivingthe lower portion of the driving gear 18, and a recess F for receivingthe lower portion of the rotary crushing roll 10.

The crushing roll 10 rotates in a clockwise di rection as shown by thearrow in Figure l and to assist the roll in performing crushing orpulverizing operations, the mill is provided with a sloping breakerplate which in the drawings is indicated generally by the referencecharacter 30. The breaker plate is made up in two separate pieces whichcomprise a base member 32 and a load engaging member 34. As illustratedin Figure 5 the base member in vertical crosssection is approximatelytriangular in shape although the triangularity of the member is reallydependent upon the provision of strengthening ribs 36 that are shownmore clearly in Figure 2. (Owing to the provision of these strengtheningribs the base member will be hereinafter considered as approximatelytriangular in vertical cross-section). It will now be observed that atopposite ends of the base member 32 there are provided integrally formedextensions 38, 40 which are adapted to rest upon the supporting members26, 28 and be secured thereto by means of bolts or other suitablefasteners 42, 44 which extend through elongated slots formed centrallyof the supports 26, 28.

The load engaging member 34, it will be observed, is provided with aflat rectangular outer surface and with a plurality of flanged andreflanged portions or members 46, 48, the upper one of which isillustrated in Figure 5 overhangs the top marginal portion of the baseand prevents downward movement of the load engaging member relatively tothe stationary base member. In order, however, still further to preventrelative movement between the two parts, there are provided a pluralityof bolts or other fasteners 50 which extend through alined openingsformed in the base and load engaging member, and by means of these twoprecautionary provisions all movement between the base 32 and the workengaging member 34 is prohibited.

As will be observed from an inspection of Figure l, the triangularity ofthe base 32 causes the load engaging member 34 to be disposed obliquelyto the vertical, whereby there is provided between the load engagingmember and the crushing roll a passageway having an upper widthwisedimension which is indicated in Figure 1 by the reference character aand a lower widthwise dimension that is indicated by the referencecharacter 2). Thus, a tapering passageway is provided between the rolland the breaker plate and the construction is such that the breakerplate is mounted rigidly with respect to the roll whereby all materialpassing between the two members must be crushed to a desired size beforeescaping from the passageway into a suitable container or receptacledisposed beneath the lower opening.

In order to vary and to control the dimensions of the passageway betweenthe breaker plate and the roll, the mill is provided with means foraffording relative adjustment between the two parts and to this end thelaterally extending projections 38, 40 formed on opposite ends of thebase mem ber 32 merge at their lower portions into horizontallyextending braces 52, 54 that are provided on their lower surfaces withserrations 56 (Figures 1 and 4) that engage serrations 58 formed on thebase members 26, 28. By virtue of these interengaging serrations orprojections the bolts 42, 44 may be loosened and the breaker plateadjusted along the base members 26 and 28 to a desired position andthereafter the bolts 42 and 44 tightened rigidly to fix the breakerplate in the position of desired adjustment. In order to obtain a morefine and precise adjustment of the breaker plate along the supports 26and 28 the pitches of the serrations carried respectively by thesupports or the breaker plate may be, as shown in Figure 4, of differentdimensions. Thus, it will be seen that the breaker plate is providedwith means for governing its adjustment relatively to the crushing roll,and the lock nuts 42, 44 constitute separate means for fixing theadjustment of the plate.

In the event that it is desired to change the degree of inclination ofthe load engaging member 34 relatively to the crushing roll 10, theformer member may be made of graduated thickness, for xampl as shown inFigure 5, the top cross-sec- I v the direction of tional portion of themember is thicker than the lower cross-sectional portion, whereby thedegree of inclination is less than it would be if the member were ofuniform thickness. So when. it is desired to change the degree ofinclination, it. is necessary only to. interchange one load engagingmember with another and the interchangeability of the membersconstitutes an important aspect of the invention, for, apart from theinclination idea it may be that in a heavy duty mill of this characterthe load engaging member will become broken or distorted to such anextent as to render it inoperative in which event it may easily bereplaced by an intact member.

Another important aspect of the invention as illustrated herein consistsin making the load engaging member of a reversible character. Thus, asillustrated in Figures 1 and 5, the lower portion of the member isformed with a flanged and refianged portion 48 as well as the upperportion and with such a provision, the holes for the reception of thebolts 50 being midway of the height, the member may be removed andreplaced with the lower extremity disposed in the same position formerlyoccupied by the upper portion. A reversal of this character also changesthe degree of inclination of the breaker plate.

It has been pointed out that in the operation of this mill, in which thebreaker plate cannot yield, that severe strains and stresses areimparted not only to the plate but to the slugger knobs with which thecrushing roll is, as usual, provided, and in order that these knobs willwithstand the severe strains to which they are subjected withoutbecoming loose and falling from the crushing roll there has beenprovided a new method or arrangement for holding them in place and it isto this that attention will now be directed.

The crushing roll 10 is provided with a multiplicity of recesses locatedin staggered relation and each of the recesses is shaped to receive aslugger knob. Now turning to Figures 6 to 9 inclusive, it will beobserved that each of the recesses is of tapering formation in adirection reverse to the direction of rotation of the roll. Thus, theoppositely disposed side walls 62, 64 of the recesses converge in arearward direction (which for the sake of convenience will behereinafter considered as the direction opposite to the rotation of theroll) and the side walls likewise as shown in Figure '7 convergeupwardly to form, in toto, a rearwardly tapering dovetailed slot.

Each of the slugger knobs 60 is provided with a body portion which inassembled condition extends outwardly from the periphery of the roll 10,as illustrated, and a base portion 66, which is shaped for interfittingengagement with one of the recesses formed in the roll. The base of eachslugger knob is of rearwardly tapering dovetail formation and fitssnugly within one of the rearwardly tapering dovetailed recesses. A slot68 extends transversely across the upward edge of each of the recessesand affords suiiicient room to permit insertion and removal of theslugger knob in the rearwardly extending opening. To the end ofpreventing accidental escape of the slugger knob, a wedge 70 or othersuitable fastening means may be inserted between the forward face of theknob and the forward wall of the slot 68. The slugger knobs 60 areprovided at their rearward extremities with portions 72 which overliethe outer surface of the roll 10 and with recesses 74 which may beutilized in loosening the slugger knobs to facilitate their removal.

In operation, it will be seen that as the slugger knobs swing downwardlyand strike the material being crushed they are driven more completelyhome as each blow is struck, and hence they remain in proper positionwithin the roll although they are subject to being removed with ease topermit replacements.

Although the invention has been described herein with particularreference to single roll crushers of the heavy duty type, it is to beappreciated that in many or all of its aspects, it may be incorporatedin other rolling mills or in other grinding or pulverizing deviceswithout in the least departing from the scope of the invention as setforth in the appended claims. Furthermore, it is to be understood thatthe invention contemplates various modifications and changes that willfrom time to time occur to those skilled in the art and it is to berecognized that such changes come squarely within the terms of theinvention as herein set forth.

Having thus described my invention, what I claim as new and desire tosecure by United States Letters Patent is:

1. A crushing mill apparatus of the character described comprising, incombination, a breaker plate and a rotary drum-like cylinder havingrecesses formed in its outer surface arranged for cooperation with thebreaker plate, the opposite side walls of said recesses being arrangedto converge upwardly and to taper rearwardly, and slugger knobs insertedin the recesses, sm'd slugger knobs comprising body portions projectingoutwardly from the recesses, and base portions having their oppositeside walls diverging downwardly to interfit with the side walls of therecess and tapering rearwardly also in interfitting relation with theside walls of the recess, whereby the slugger knobs are dovetailedagainst radial displacement and are wedged against circumferentialdisplacement in a direction reverse to the direction of rotation of theroll.

2. A crushing mill apparatus of the character described comprising, incombination, a breaker plate and a rotary drum-like cylinder havingrecesses formed in its outer surface arranged for cooperation with thebreaker plate, the opposite side walls of said recesses being arrangedto converge upwardly and to taper rearwardly, and slugger knobs insertedinto the recesses, said slugger knobs comprising body portions ofapproximately rectangular shape projecting outwardly from the recessesand base portions having their opposite side Walls diverging downwardlyin interfitting relation with the side walls of the recess and taperingrearwardly also to interfit with the side walls of the recess wherebythe slugger knobs are dovetailed against radial displacement and wedgedagainst circumferential displacement in a direction reverse to thedirection of rotation of the roll, the length of said recesses beingslightly greater than the length of said base portions to permitinsertion and removal of the slugger knobs.

3. In a crusher, a rotary crusher roll having a plurality of recessesformed in its outer sur face, the opposite side walls of each of saidrecesses being formed to converge radially outward with respect to theroll and to converge circumferentially of the roll in a directionopposite to the direction of rotation of the roll and crusher teethremovably inserted in said recesses, said teeth including portionsprojecting outwardly with respect to the outer surface of said roll andattaching portions in said recesses, said attaching portions havingopposite side walls formed to converge radially outward with respect tosaid roll and to converge circumferentially of the roll in a directionopposite to the direction of rotation of the roll whereby said teeth aredovetailed against radial displacement and are wedged againstcircumferential displacement.

4. In a crusher, a rotary crusher roll having a plurality of recessesformed in its outer surface, the opposite side walls of each of saidrecesses being formed to converge radially outward with respect to theroll and to converge circumferentially of the roll in a directionopposite to the direction of rotation of the roll and crusher teethremovably inserted in said recesses, said teeth including portionsprojecting outwardly with respect to the outer surface of said roll andattaching portions in said recesses, said attaching portions havingopposite side walls formed to converge radially outward with respect tosaid roll and to converge circumferentially of the roll in a directionopposite to the direction of rotation of the roll whereby said teeth aredovetailed against radial displacement and are wedged againstcircumferential displacement, the widths of said recessescircumferentially of said roll being slightly greater than the width ofsaid attaching portions of said teeth to permit insertion and removal ofsaid teeth.

' M. B. DAVIS.

